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DEBT - Long-term Debt Schedule (Details) - USD ($)	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2019
DEBT
Total Debt	$ 416,874,000	$ 355,716,000
Less: Unamortized debt issuance costs	(4,615,000)	(3,481,000)
Less: Current Maturities of Long-term Debt	(66,194,000)	(57,548,000)
Total Long-term Debt, net	346,065,000	294,687,000
Notes payable under the Company's 2019-1 EETC agreement \| Notes payable
DEBT
Total Debt	$ 176,697,000	176,697,000
Face amount				$ 248,587,000
Weighted average interest rate	4.73%
Notes payable under the Company's 2019-1 EETC agreement \| Minimum \| Notes payable
DEBT
Interest rate				4.13%
Notes payable under the Company's 2019-1 EETC agreement \| Maximum \| Notes payable
DEBT
Interest rate				6.95%
Notes payable under the Company's 2022-1 EETC agreement \| Notes payable
DEBT
Total Debt	$ 168,897,000	179,019,000
Face amount			$ 188,277,000
Weighted average interest rate	5.06%
Notes payable under the Company's 2022-1 EETC agreement \| Minimum \| Notes payable
DEBT
Interest rate			4.84%
Notes payable under the Company's 2022-1 EETC agreement \| Maximum \| Notes payable
DEBT
Interest rate			5.75%
Delayed Draw Term Loan Facility
DEBT
Total Debt	$ 71,280,000	$ 0